Sound recording and reproducing device



Spt. 13, 1932. 1. WALKER 1,877,485

SOUND RECORDING AND REPRODUCING DEVICE Filed June 29, 1928 2 Sheets-Sheet l a NJ w E ...Nm W o o .I W M xv 1 .UU m wmf/lo o M o o Q l N I l @uw. m M NN M uw mw E l WN. 4 i MW m o o w\.\ nl m 4 o o H A M n* M hw m lv l.. E m wx E@ N N w W l u .m

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13, 1932 J. l., WALKER 1,877,485

SOUND RECORDING AND REPRODUCING DEVICE Filed June 29, 1928 2 Sheets-Sheet 2 u W L m Sw ,SQ

Patented Sept. 13, 1932 PATENT OFFICE .mcg L. WALKER, or DALLAS, TEXAS SOUND RECORDING AND REPRODUCING DEVICE Application lcd .Tune 29,

This invention relates to newv and useful improvements in recording andreproducing sound waves.

The invention has to do with that class of recording and reproducing devices which involve the use of electrical, optical and mechanical means, and in which the sound record is to be transferred from one type of t record to another type of record.

This invention has for its principal objects the following,- V

To furnish a means of controlling a cutting tool which will be positive and unaffected by c the work performed by it and which will not vary its cutting depth even when ystriking hard and soft spots in the material to be cut.

To cut equally well'both'shallow and deep cuts without variation and be rigidly mounted to prevent a tendency to chatter.

To prevent the rounding off of sound'waves when recorded by it due to inertia, friction or high frequency.

To provide a method for cutting or wearing away of a hard material such as celluloid film in such a manner that the sound waves will be faithfully recorded in respect to their proper depth and smoothness of surface.

To decrease the frequency of sound variations during the process of transferring the said variations from one filmto another by slowing down the films whereby a cutting tool will produce a finer cut and the moving parts will not be affected by mechanical and electrical inertia.

To produce a type of record which may be used with a standard motion picture film and which will not occupy any of the valuable space now used for the regular picture.

To duplicate the sound record upon both edges of the film so that when one sound track becomes damaged the other may be used or in case part of the Atalking on a film may be censored and ordered erased the other side may be used which might contain only music. Thus all music could be recorded on one edge of a film and talking on the other edge if desired and an erasing machine which might consist of a small grinding machine be used to grind off the sound variations where 50 desired.

1928. Serial No. 289,256.

To produce a type of recording means which will not require changing of needles in the useof the records and a long reel run or reproduced without stopping for a new needle.

To produce a type of reproducing stylus that may have a new surface brought into contact with the sound track or grooves while in operation without a change being heard ink V the reproduction of the sounds, and one which cannot fall out ofthe sound groove as a needle might. f

To arrange the leverage ratio where the cutting tool is connected so that anyk redetermined amounty of amplification may e had by cutting a depth corresponding to the amplification desired. Also to increase or decrease the magnification of a light image on a screen for regulating the amplification, where the lever follows a light image as a pattern for recording sound waves.

To provide ameans for polishing the sound grooves milled upon the edge of a motion picture film so that surface noises or scratching will be eliminated. f 75 To provide means whereby the tool cutting into the edge of the film may be controlled either manually or automatically.

`To provide means of transferringy Sound waves from one film containing a finished photographic sound record to another film whereby both films may be run at the same speed or at a certain ratio of speed, and synchronized with a printed and developed motion picture.

To use vacuum tubes such as used in radio amplifiers for amplifying the current controlled by a selenium cell so as to amplify the sound variations.

With these and other objects in view I will n describe my method of carrying out the invention.

A beam of light from a steady source is directed upon a photographic sound record g5 film, behind which is an apertured plate containing a very narrow opening, said plate preventing the passage of the light directed upon the film excepting at a very small area longitudinally of said film and preventing its passage transversely excepting at the portion which contains the sound variations.

Thus the light in passing through the developed iihn sound record is allowed to pass through only a small portion of a sound wave at a time. This light after passing through said developed film sound record impinges upon a seleniumcell or other device capable of varying an electric current in proportion to the amount ot light striking it.

As the developed film sound record moves slowly longitudinally the light passing through the various sound waves cause the selenium cell to receive more or less light, depending upon the opacity of the iilm at the portion directly in line with the aperture plate. This 'ariation in illumination causes a corresponding variation in the resistance of the selenium cell which in turn regulates the amount oli current allowed to pass through it.

Connected to the selenium cell receiving light from the sound record film is a circuit containing a battery and electro-solenoid. This solenoid has a plunger of soft iron balanced near its magnetic center by two coil springs which tend to hold the plunger at rest at a certain point when the current is steady within its Coils, and moves up and down when the current is rising and falling. Mounted upon the top of this plunger is an opaque shutter member containing a small rectangular opening and is arranged to be illuminated from one side by an incandescent lamp. The other side of said shutter is arranged with a projecting lens similar to that used in projecting regular motion pictures. This projecting lens collects light from the illuminated rectangular opening and projects an image of it upon a screen located at some distance from said lens.

As long as there is no change in the illumination of the selenium cell there will be no change in the position of' the light image upon the screen, but as soon as the variations in the developed iilm sound record change the illumination upon the selenium cell the spot oi' light on the screen will change its position.

The variations in the position of the light image upon the screen will be proportional to the variations in the sound wave record, and to reproduce the same values of fluctuations upon another lm av long lever pivoted near one end is arranged to regulate the amount ot movement of a cutting device connected thereto at its short end. The long end otthis lever or the end farther from the pivot point is moved up and down as the image of light on the screen moves up and down. Thus the cutting device, if consisting l. of a grinding wheel rotated by a motor, is

operated in and out against the edge of a regular moving picture film, and said lm if moving longitudinally but held so that itcannot move transversely, will receive notches upon its edge corresponding to the amountV of movement of the lever and the frequency of its movements up and down.

On account of the distance from the pivot point to the end of the lever which is arranged to follow the image of light on the screen, the lever will exert a very powerful force at its short end even il moved up and down with a light grasp of the hand at the long end.

Thus it will be seen that it would be almost impossible to affect the depth or character of the cut upon the film even it the cutter were cutting into'a very soft spot at one instant and a very hard one the next.

The end of the lever which is designed to follow the image of light on the screen may be moved up and down by grasping the end oi the lever in the hand and watching the image in its movements on the screen and following them, always keeping the end of the lever pointing toward the light image.

For faster operation and more positive manipulation I have arranged a device upon the end of the lever which consists ol a small screen or shield which contains two openings approximately the width of the beam of light apart and which contain condensing lenses which collect light When the light image is inv line to strike them.

At the focal point of these two lenses two selenium cells are mounted. Each of the-se selenium cells is connected to a. circuit containing a battery and an electro-magnet relay. The relays are adjusted so that a retractile spring holds their armatures open against the pull of the electro-magnet when the selenium cell is receiving no light from the projection lens. However, the moment that eitherv selenium cell is illuminated by all or a portion of the light image striking it, the resistance falls and the armature ot' the relay is operated. The operating or closing of the armature of the relay establishes a eircuit through another battery to a motor and causes its armature to rotate. This motor is connected through gearing and a screw arrangement attached to the lever so that the lever is either ope ated up or down depend infT upon the direction of rotation of the motor. The motor is of the reversible type and has the two relays connected to it in suffh a manner that the relay controlled by the upper selenium cell will cause it to elevate the lever when the upper selenium cell is illuminated and will operate. in an opposite direction and lower the lever when the lower selenium cell is illuminated.

In operation the motor is operated by manually operating one of the armatures of one of the relays, depending upon whether the lever is below or above the light innige, imtil the light image rests midway between the two condensing lenses. After this point is reached the light image will automatically remain between the two lenses.

If the light image starts upward the top selenium cell willv cause its relay to operate and automatically elevate the lever carrying the two condensing lenses andthe two sel'enium cells. The lever will continue to oper-r ate until the beam of light stops its upward travel. After the beam of lighthas stopped in its upward travel the motor continues to operate the lever up until the top selenium cell receives no more light. kThe top selenium cell being darkened by the lever elevating until it is out of the path of the light, the

relay opens its contact and the motor stops.y

' lower lens receives no more light. Thus it will be seen that the beam of light always stays approximately centered between the upper and lower selenium cells.

From this itwill be seen that as soon as the beam of light moves up or down in accordance with the fluctuations in a sound wave record which controls the solenoid and shutter the lever also moves up or down and follows the light image as long as it is in j motion.

The beam of light may go from one extreme at the top to the extreme bottom one time and the .next time it may only go from the extreme top kto a midway point and then turn back. No matter where the light stops and starts back in the opposite direction the lever will also stop and start back with it.

The short end of the lever is arranged to be used with different kinds of cutters depending upon the character of material to be cut as well as the'form ofthe material to be cut. f

For cutting into ,the edge of a celluloid film a rotating motor is connected to a hinged support and carries a small grinding wheel with avery thin edge and of a very line grain. This wheel is of such a character that it will leave a comparatively smooth surface to the edge of the film after it has cut into it so that no scratches will be heard in the reproducer when the record is reproduced after being made. The speed of the wheel is such that no damage will be done to the film from excessive heat due to friction. This rotating wheel is made to act against 'the edge of the film in accordance with the movements of the short end of the lever which Vfollows the beam of light.

yBelow the wheel which wears away the film in accordance with the variations in a sound wave record film is another wheel, arranged to rotate by a hinged motor. This second wheel is of the same shape as the first wheel but of a still liner grain such as an oil stone of the circula-r type.` Ak small spring is attached to the second motor which I will designate as a polishingmotor and causes a very slight but constant pressure of the revolving polishing wheel against the sound grooves cut into the film by the upper wheel. This spring can be unhooked if desired and it is thought to be unnecessary where the cutting is done at a very slow speed.

Vhere fast cutting is desired it is obvious that the sound controlled wheel should be a fast cutting wheel and will necessarily be of comparatively coarse grain. Then the polishing wheel will be necessary to remove the grain marks from the sound grooves.

It is very essential for the best results,

that the sound variations be spaced far apart upon the original sound record film and later reduced to occupy a smaller space on another film for synchronizing with a motion picture running at the regular speed. Thus the original sound record film should be run, during the recording process, three times faster than the regular speed. In this way t-he sound variations, instead of appearing as hair lines on the film, will appear as relatively wide l.

bands. This type of record is more suitable to my transferring process and produces a much better record for reproducing should it be desired to use it for a phonograph record as there is less overlapping of variations Zar.:

at high frequencies.

It is obvioustherefore that the system of recording sound waves which allows the fastest travel of the film during the recording process is the best record for transferring to the edge of a film or to any other material by the process disclosed in this application.

The invention may be more readily understood by a reading of the following specification and by reference to the accompanying drawings, which are more or less diagrammatical, in which an example of the invention is shown.

Fig. 1 shows the theory of the process in 'ha detail where the lever is operated manually.

Fig. 2 shows a detail of the sound notches as they will appeal-,when magnified, upon the edge of the regular motion picture film which is to be projected upon the screen for being viewed by the audience. Also the circular cutter' which is moved in and out of the edge of the film. In accordance with the movements of the lever connected with it (not shown). f y

Fig. 3 shows a detail of the lever operating automatically from a beam of light, in which both the lever andbeam of light both are shown broken away. r(It being understood that this lever is similar to that shown in Fig. 1 excepting at its end where the beam of light strikes it).

Fig. 4 shows one type of developed film sound record which may be used as a controlling pattern to produce the type of record shown in Fig. 2.

Fig. 5 shows a view of' the shutter operated by the solenoid and shows the solenoid plunger broken away.

Fig. 6 shows the recording lever connected to a sharp pointed tool which is firmly attached to its support, instead of a rotating wheel, and is shown engaging a wax cylinder blank record.

Fig. 7 shows a detail of the gearing whereby fihns 4 and 22 may be run at a different speed ratio than that shown in Fig. 1.

In the drawings numeral 1 designates an illuminating lamp connected to a steady source of battery 2. Numeral 3 designates a condensing lens for concentrating the light 'ays upon the developed film sound record 4. Nume al 5 designates a shield for preventing the light from passing through the developed film sound record to the selenium cell 6 except at a very small aperture so that only a portion of a. sound variation will be acted upon at a time. Numeral T designates a battery connected to selenium cell 6 and to solenoid S, which is designed to operate the plunger 9 up and down against the tension of springs A and A. Numeral 9A designates an opaque shutter with a small rectangular opening near its center, and is illuminated from one side by a beam of light concentrated by condensing lenses 10 from lalnp 11. Numeral 12 designates a battery for operating lamp 11. Numeral 13 designates a projecting lens such as is used in motion picture projecting machines and projects an image of rthe illuminated rectangular opening in shutter 9.5L upon screen 14. Letter B shows the path of a beam of light from the projecting lens to the screen. Numeral 15 shows a lever arranged to follow tl e beam of light on screen 14 as it moves up and down in accordance with the movements of shutter 9A and the variations in the sound wave record film. Letter C designates a hand and arm of an operator who manually operates the lever 15 up and down as the beam of light travels up and down on the screen 14. Numeral 16 designates a fulcrum post for Supporting the lulerumed lever 15. Letter D designates a spring for holding the lever' 15 upon its support 16. Numeral 17 designates a connecting link for connecting lever 15 to a hinged motor 13 carrying a circular grinding wheel 19 upon its sha-ft 20. Motor 18 being hinged or pivoted to a support at point 21 is allowed to swing in and out in accordance with the movements of lever 15 and causes grinding wheel 19 to bear against a developed picture film 22, which contains a regular printed picture ready to receive the sound grooves upon its edge. Numeral 23 designates a polishing motor carrying upon its shaft 24 a. polishing wheel 25. Motor 23 is supported similar to motor 18 and is hinged at point 26. Numeral 27 designates a spring for causing a light pressure of grinding wheel 25 against the picture film 22. This pressure should be just sufficient to polish the grooves cut by wheel 19. Numeral 28 designates a motor for producing, through worm 29 and gear 30A, slow travel of films 4 and 22. Numerals 30 and 3l designate bevel gears for transmitting motion from shaft 32 to shaft 33. It is understood that these gears may be each the same size for producing the same speed on both films as shown in Fig. 1 or one may be smaller than the other for producing a different `at-io of speed between the two fihns an example of which is shown in Fig. 9 where the developed film sound record film 4 is arranged to travel at twice the speed of the film 22 which is to receive the sound notches. Belmid bevel gear 31 is shown, in dotted lines7 a sprocket wheel 56 for engaging with the sprocket holes in film 4 to move it downward. Numeral 57 shows the sprocket wheel for engaging the sprocket holes in film 22 to move it downward at the same time that film 4 is moved downward by sprocket 56 connected with it through bevel gears 3() and 31. Letters F and Gr designate rollers over which the films are guided from reels (not shown). Films 4 and 22 are shown broken away at the top and bottoln and it is understood that suitable reels with take-up means are provided for the films as is done in common practice. Sprocket 56 is fixed to sha-ft 33 and sprocket 57 is fixed to shaft 32. Suitable bearings are arranged to support the various parts and are not shown in the drawings in all cases as too much detail would be confusing and this device is intended to be illustrated more or less diagrammatically. Numeral 34 designates a plate for supporting film 22 against the pressure of wheels 19 and 25 so that the film will have no transverse movement and the grinding wheel 19 will cut into film 22 a definite depth depending upon the movement of the lever 15 or 15A. Numeral designates a battery which furnishes current for operating electric motors 18, 23 and 28. Letter E designates a spring for preventing lost motion in connecting lever 15 with the framework of motor 18. Numeral 36 in Fig. 2 shows a sound groove on the edge of film 22 after the grinding wheel 19 has been controlled by the variation in a sound wave record and ground away the celluloid. Numeral 19 in Fig. 2 shows the cutter or grinding wheel in contact with the film and producing a sound groove. Numeral 5S shows a large bevel gear. mounted upon shaft 32 (shown broken away) and a small bevel gear 59 mounted upon shaft in mesh with each other for operating the film 4 at twice the speed of film 22. This is to be used where the original sounds are recorded uponga film running exactly twice as fast as another film upon which animated pictures are being taken. It is obvious that any ratio of gearing may be used to match the two films so that the sound waves notched upon the edge of a motion picture film will be in synchronism with the movements recorded thereon and which are to be viewed with the eye after projecting upon a screen.

In Fig. 2 the grooves shown yare amplified many times more than the sound grooves on an ordinary phonograph record which as is well known cannot be seen very well with the naked eye. What I mean here by sound grooves on an ordinary record isthe variable out that produces sound waves when the reproducing needle follows them and notthe guiding grooves which can be seen` in a spiral on the disc record. It is obvious that by connecting the lever 15 to the swinging motor at different points of leverage'the movement can be diminished to any extent for; producing less amplification than that shown or it can be increased. No invention `would be covered in an adjusting means, but the invention lies in the broad principle of reducing the movement of the long lever whereby a powerful control is had. While the sprocket holes shown in the drawings are not exactly like the regular sprocket holes in ar moving picture film, they are intended to represent regular standard film sprocket holes. Also the film 22 in this system is shown in the drawings without pictures printed and developed on it, but it is understood that the film has been printed and developed in the usual manner and is ready to be projected upon the screen as soon as the sound variations are recorded thereon. .Y

Fig. 3 shows an automatic method of following the beam of light as it moves up Land down in accordance with the fluctuations in a sound wave record film and in which, nu meral 37 shows a lens arranged to concentrate the light falling upon it, when the beam of light from the projection lens strikes it. Numeral 38 designates a selenium cell arranged to receive the concentrated rays of light from lens 37. Numeral 39 designates a relay connected to selenium cell 38 in an electrical circuit kwith a. batter 40. In operation selenium cell 38, when illuminated by beam of light B, lowers its resistance and allows more current to flow through coils of relay 39 than normally flow through it. The current fiowing through coils of relay 39, when the selenium cell is illuminated, closes the armature 41 againstfthe tension of spring 42 and causes armature 41 to make contact with contact post 43. This ysets up an electrical circuit through battery `44 to motor 45 at its two upper connectionsand operates it in a direction which elevates screw 46 through gears 47 and 48. Thus the motor operates in a direction that `will elevate screw 46 at any time that selenium-cell 38 is illuminated. The top of screw 46 is flexibly connected to lever A which is connected to the cutting device described in Fig. 1 similar to lever 15 with which it is interchangeable.` Let us imagine that selenium cell 38 is in the path of the focussed light B, then the motor will immediately elevate the lever 15A until the light no longer strikes it. If the beam of light travels slowly upward the selenium cell 38 will again receive li ht and operate the motor 45 through the (Iescribed circuit and elevate the lever 15A. This movement will continue as long as the beam of light moves upward. As soon as the beam of light stops the motor will continue to operate onl until the lever 15A has been elevated enoug to elevate the selenium cell 38 above the beam of light. The selenium cell 38, no longer receiving light from beam B, will increase its resistance and open relay 39 and stop the motor 45.

Thus it will be seen that the beam of .light moving upward causes the lever 15A to also move upward and when the beamof` light stops the lever also stops. I will now describe the sequence of operations when the light beam B travels downward. Light beam B is centered between lenses 37 and 49. Both relays 39 and 51 have their armatures open and the motor is at rest. Beam B starts ,moving downward. Lens 49 receives light and concentrates it upon selenium cell y50. kThe resistance falls in selenium cell 50 allowing more current to fiow through the coils of relay 51 from battery 40A. IThe greater flow of ycurrent through coils of relay 51 increases the magnetic pull on armature 52 overcoming y the pull of sprlng 55. Armature 52 makes contact with post 53 completing a circuit through battery 54 to the lower connections on motor 45. The armature of motor 45 rotates in an opposite direction from that previously described and lowers screw 46 and leverf'15A. (Motor continues to operate until the beam of lightfrom beam B no longer illuminates selenium cell.50.) Beam of light stops its downward movement. Lever 15A is lowered to the point where the Vselenium cell receives no more light from beam B. Resistance in selenium cell increases and decreases the pull on armature 52. Spring 55 overcomes the magnetic pull of magnet coil of relay 51. Armature 52 breaks Contact with post 53. Motor 45 stops rotating and lever 15A becomes stationary.

If the beam of light suddenly reverses its direction after travelling downward it will illuminate the top lens 37 and cause the motor to operate in an opposite direction to that which it was going while the lever was being lowered. This being done by the lowering relay going open and the elevatingrelay closl f ing the current from the control'of the ele'- vating relay will flow through the windings of motor l5 and tend to reverse it. The motor will then stop rotating in the direction that it had been rotating sooner than if left to stop of its own accord as the reversing current will act as a brake. Thus the response will be very rapid when the beam of light changes its direction of travel and no matter where the beam of light stops and turns back in the opposite direction the lever will also just as quickly stop and turn back.

rIhe screw elevating means is shown simply as an example and it is understood that there are various ways of elevating lever 15A which might be used and still be covered by this patent. One method would be substituting a rack and pinion method of elevating and lowering the lever where it is desired to obtain a faster movement than a screw arrangement would permit of. While it is desired to get protection on all of the method disclosed in this speciiication, it is my object mainly to secure basic claims on the novel principle involved in controlling a cutting device by an irreversible7 means and slowing down sound variations to a point where they may be manipulated in a positive manner for controlling a cutting device and give time for producing a cut that will be more accurate and smooth. Also one of the principal points which I desire to protect with claims is the novel means of using the edge of the film whereby none of the valuable part of the film is robbed to make room for the sound record.

Fig. 4 shows one type of photographic sound record iilm which may be used with the herein described method. As I have patents covering the production of this type of record as well as others which might be used as a pattern for controlling the cutting device, it is not considered necessary to go into details regarding the character which I have described as a photographic sound record film.

Fig. 5 shows a front view of the shutter member 9 showing an aperture 9A which is illuminated for projection upon the screen. The lower portion shows the top spring A and the plunger 9 broken away.

In Fig. 6 numeral 60 designates a wax cylinder blank record such as is used for recording upon in dictating machines such as the dictaphone and ediphone as well as the Edison home phonograph. Numeral 6l designates a drmn upon which the blank record 60 iits. Both the drum an d the record 60 are arranged to be rotated by a suitable means and geared to a sprocket wheel arranged to move a photographic sound record film. Numeral 62 designates a cutting tool vsupported by tool post 63 pivoted at point 64 and connected with lever 15A by connecting link 17. Letter E designates a spring -for taking up any lost motion which might occur in the pivot points between tool post G3 and lever 15A. Lever 15A is shown broken away and is the same as the lever' shown in Fig. 3 which is arranged to follow a beam of light in accordance with the variations in a sound wave record film. Lever 15A connected to cutter 62 causes the soft wax blank record 60 to be cut away by the movements of it and as the lever is travelling up and down in accordance with the variations in a sound wave record the tool will cut into the wax in accordance with the variations in the sound wave record and produce a hill and dale type of record such as is generally used on cylinder machines. The operation of this device is obvious when the explanation regarding the operation of Fig. l is understood, therefore it is thought that no more explanation is necessary. Fig. G shows a cylinder but it is obvious that a. disc could also be cut by the control of a lever and a cutting point to dig into the disc. Both the disc and cylinder types of records and the process of recording is old whereby a groove is cut to guide the reproducing needle and said groove is made irregular by the cutting o' the sound waves into the groove. For that reason no details will be shown regarding these types of records as my device simply pertains to the method of put-ting the sound variations upon these records mechanically instead of making the sound variations record direct to the diaphragm and cutting point controlled by it.

Fig. 7 represents the reproducer and numeral 22 designates the sound record film. This film is shown in relation to the reproducing stylus 65 to require a movement upward to cause the stylus to operate correctly. As the film moves upward stylus 65 mounted upon reproducing lever rides in and out of the sound notches on film 22 and causes vibrations of a diaphragm as in the regular reproducer on aphonograph. Numeral G7 designates a regular phonograph reproducer and 68 designates a horn, or resonator. There are only two new features whereby this reproducer diifers from an ordinary phonograph reproducingr device. One ot these is the stylus which replaces the regular needle and which is a wide flat piece of steel or other material which has a small round shank on one end for being inserted in the receptacle for needles and clamped as regular needles are clamped by a set screw. The other is the carriage which is arranged to move upon a slide rod and aregulating screw, so that the position of the stylus may be changed while sounds are being reproduced. Numeral. (if) represents a thumb screw and numeral 70 designates a guide rod. By referring to Fig. 8 the thumbscrew will be seen supporting a threaded carriage 71 designed to be moved between two supporting brackets when said thumbscrew is rotated. Thumbscrew 69 is arranged to rotate in brackets H and I without end play. In Fig. 8 film 22 is shown with the reproducing stylus fed over to a point where the edge of said stylus has been half used up considering that the reproducing was started with the film bearing at one end of it.

l. In a device of the Character described, means for causing variations in opacity of a sound record film to vary the value of an eiectric current, means for producing variations in a shutter position by said variations in opacity, means for projecting a light image of said variations of said shutter positions, means for producing travel of a lever in accordance with the travel of said light image of said shut-ter and means for mechanically producing sound variations in accordance with the variations in position of said lever and in accordance with the variations in said sound record film varying in opacity.

2. In a device of the character described, means for moving a developed film sound record and a blank Celluloid film simultaneously, means for causing a beam of light to pass through said developed film sound record and illuminate a light sensitive device, means for changing the position of a shutter member by said beam of light acting upon said light sensitive device and Controlling said posit-ion by said variations in opacity of said sound record, means for projecting an image of light from said shutter member, means for causing synchronized movement of one end of a pivoted lever, having one long and one short end from its pivot point, with said image of light, means for connecting a cutting, or friction, device to the other end of said lever, means for causing varying movements of said lever to vary the wearing away process of said blank Celluloid film by said cutting, or friction, device in accordance with the variations in opacity of said developed film sound record and means for polishing said Celluloid film after said wearing away process.

3. In a device of the character described, a driving means rotating two film sprocket wheels at a relatively slow speed, one of which is arranged to carry a developed film sound record varying in opacity and the other to carry a Celluloid film ready to have sound waves recorded upon it, means for causing both films to travel at the same relative speed, means for causing light from a steady light source to penetrate said sound record varying in opacity and impinge upon a light sensitive electric cell, means for electrically operating a shutter member by said light sensitive electric cell, an adjusting means for adjusting said shutter member so that variations injopacity of said sound record will cause variations in position of said shutter member, a light source acting upon said shut-ter to illuminate it, a lens arranged to collect light from said shutter and project an image of it to a distance, a pivoted lever having a long and short end, two light sensitive cells mounted upon the long end of said lever and arranged to be in the path of the said projected light image and arranged so that the space between the said light sensitive cells slightly exceeds the area of the said light image, an electrical circuit with battery connected to each of said light sensitive cells, a circuit closing relay in series with each of said circuits, an adjusting means for adjusting said relays so they will not operate their tongues unless the said light sensitive cells are illuminated by said light image, an electrical circuit with battery connected to the tongues of each of said relays and a motor with two separate windings connected to the tongue circuits of said relays and arranged to turn in one direction from one of said tongue circuits and in the other direction from the other tongue circuit, means for connecting said motor to said lever causing movement of the said motor to move said lever to a position following said light image, means for connecting to the shorter end of said lever a rotating means having a thin disc arranged to wear away the edge of a Celluloid film, and means for polishing said Celluloid film after said wearing away process.

.J ACK L. WALKER. 

